Unit 1 2016 Flashcards
what happens when an atom loses/gains an electron?
It becomes charged, an ion.
Where is the lowest energy level?
closest to the nulceus
Why do atoms react?
because they don’t have a full outer shell
What is ionic bonding?
metal loses electrons to form a positive ion and non-metal gains electrons to form a negative ion. Then opposite charges.
What is covalent bonding?
Two non-metals share electrons
Advantages of limestone quarries
provides jobs, crater could be used for lesisure activities (s), crater could be used as a nature reserve or landfill (En), money made from cement/ other building material(E).
Disadvantages of limestone quarries
Loud, lorries are not ecofriendly and may wear away the verges, the jobs are not permanent, costs a lot to set up.
What is the limestone cycle?
CaCO3 -> CaO -> Ca(OH)2(s) -> Ca(OH)2(aq)
What is an ore?
Rock that contains enough metal to make extraction economically viable.
What is reduction with carbon?
Oxygen is removed by heating with carbon in a blast furnace (depends on whether the metal is below carbon on the reactivity series)
`What is electrolysis?
Used to purify copper by splitting it up with electricity (expensive) Copper moves to the negatively charged side of pure copper.
What is a displacement reaction?
Put a reactive metal in a solution of dissolved metal compound. The reactive metal will replace the less reactive metal in the compound.
What is bioleaching?
Uses bacteria to separate copper from copper sulphate
what is phytomining?
grows plants in soil that contains copper then burning the plants to get the copper.
What are some properties of metals?
Strong, ductile, Malleable and conducts heat + electricity
What is an alloy?
a mixture of two elements, one of which being a metal.
What are properties of alloys?
harder because different sized atoms stop layers sliding.
What are the 3 different types of steel?
Low Carbon, High Carbon and Stainless Steel.
What is crude oil?
A mixture of hydrocarbons. No chemical bond so the keep their original properties (e.g. condensing point) meaning the mixture can be separated by physical methods.
What is fractional distillation?
A way of splitting up crude oil into different length hydrocarbons.
What is an Alkane?
Saturated (carbon has as many possible bonds with hydrogen) CnH2n+2
What happen it the chain is short?
It is runny, volatile and flammable.
What does burning fossils fuels make?
Carbon dioxide (global warming), particulates (global dimming), sulfur dioxide if there are impurities (acid rain) and carbon monoxide if there is not enough oxygen.
What are some alternative fuels?
Ethanol, Biodiesle and hydrogen gas
What is cracking?
When the long hydrocarbon chain is broken into shorter ones. It is a thermal decomposition reaction and the long chain is passed over aluminium oxide at 500 degrees.
How can ethanol be made?
By hydrating ethene or by fermentation
What is polymerisation?
Joining many monomers to make a long chain.
How can you extract plant oils?
By crushing or distillation
What do vegetable oils provide?
energy, nutrients, fatty acids, flavour, higher boiling points.
What do unsaturated oils do in bromine water?
decolourise it.
What is hydrogenation?
unsaturated oils being harderened by adding hydrogen in the presence of a nickel catalyst at 60 degrees.
What is an emulsion?
lots of droplets of one liquid suspended in another.
What is evidence for wegners theory of continental drift?
1) Fossils are similar on opposite sides of the Atlantic ocean
2) ‘jigsaw fit’
3) Matching layer of rock in both continents
What is the evolution of the atomphere?
1) Lots of volcanic eruptions. mostly CO2, Methane and Ammonia.
2) Green plants +algae evolved and produced oxygen by photosynthesis.
3) build-up of oxygen allowed complex organisms and the ozone layer to form.
What is the primordial soup/
amino acid formed organic matter and simple organisms.
How do you fractionally distill air?
Filter, Liquefaction, and distillation
